Double twist twisting process and apparatus



Jan. 3, 1967 KARL-HEINZ REHN DOUBLE TWIST TWISTING PROCESS AND APPARATUS Filed Nov. 20, 1964 5 Sheets-Sheet l INVENTOR. KARL-HEINZ REHN @w/iaa ATT YS 1967 KARL"HEINZ REHN 3,295,306

DOUBLE TWIST TWIS'IING PROCESS AND APPARATUS Filed Nov. 20, 1964 5 Sheets-Sheet 2 l r j 27 IO FIG. 6

I INVENTOR. :4 KARL-HEINZ REHN ATT'YS 1967 KARLHEINZ REHN DOUBLE TWIST TWISTING PROCESS AND APPARATUS s Sheets-Sheet 5 Filed Nov. 20, 1964 FIG? INVENTOR: KARL-HEINZ REHN BY 04M" 0%1Z5 g J ,2 ATT'YS United States fine 3,295,306 DOUBLE TWIST TWlSTllNG PRUCESS AND APPARATUS Karl-Heinz Rehn, Remscheid-Lennep, Germany, assignor to Banner Maschinenfabrik Aktienges, Wuppertal- Oberbarmen, Germany Filed Nov. 20, 1964, Ser. No. 412,632 Claims priority, applicatign Germany, Nov. 30, 1963,

4,466 14 Claims. (Cl. 57-58.83)

This invention relates to a double twist thread twisting process, sometimes referred to as a two-for-one twisting process, wherein a superficial coating of a lubricating agent is applied to the twisted thread, and the invention is further directer to apparatus for the execution of this process.

For the purpose of twisting thread, it is now conventional to employ a double twist twisting device whereby the thread is drawn off over-head or tangentially from a stationary or rotatable delivery bobbin and is then conducted downwardly through a longitudinal bore of a hollow bobbin spindle. The thread is then drawn off radially from the lower end of the spindle over a rotating storage or accumulator disc and then with the formation of an outer thread balloon, the thread is conducted upwardly through a guide loop or eye positioned above the bobbin and spindle, the thread finally being drawn onto a preliminary draw-off device or directly onto a take-up or storage reel. In this manner, a double twist is imparted to the thread. Where the thread is drawn from the bobbin over-head into the inlet of the hollow spindle, there is usually formed a relatively small, so-called inner thread balloon rotating inside the outer thread balloon which is characteristic of the double twist twisting process. In order to limit or constrict the rotating pattern of the outer thread balloon, there is frequently employed a mantle in the form of a ring, cage or cylinder shell concentric with the spindle axis. This mantle serves to reduce thread tension in the balloon. The double twist device can be used to twist a single thread, or it is also possible for several threads to be drawn off and twisted together from one plying bobbin or from two or more individual bobbins superimposed one above the other on the hollow spindle.

In most instances, the thread is supplied from the delivery bobbins in a dry state to the double twist twisting spindles. However, it has also been proposed that such double twist twisting devices also be employed for wet twisting, in which process the thread is completely soaked or impregnated with water or other moistening agents before twisting the thread. This wet twist process is used in order to obtain a twisted thread or yarn which is very supple and flexible in any subsequent processing. The moistening or impregnation must be accomplished while the thread or yarn is in a relatively untwisted open state, or else the desired properties of flexibility cannot be achieved. Thus, in carrying out the wet process, it is feasible to impregnate the thread or yarn before it has been wound on the delivery bobbin used in the twisting process or even after the thread is drawn off this delivery bobbin, provided that impregnation occurs before the thread emerges from the spindle. Once the thread is twisted, it loses most of its absorbency, and the application of the moistening agent would not bring about the effects desired in a wet twisting process.

The present invention is concerned with a problem which is entirely distinct from that sought to be solved by the wet twisting process. More particularly, the present invention is concerned with a difficult problem which arises when using a double twist device for twisting threads or yarns composed of staple fibers, including threads or yarns of natural or synthetic fibers or mixtures thereof and also including such specific materials as cotton or wool in which the fibers have a finite length or mixed yarns of natural and synthetic fibers such as wool and polyethylene terephthalate or nylon fibers. During the double twisting of such thread and especially in the vicinity of the outer thread balloon pattern, there arises a very undesirable and substantial accumulation of flying fibers or dust caused primarily by small protruding fiber ends which have been broken off from the thread or yarn. These relatively small broken particles of fibers are dispersed in a turbulent manner by the flowing air stream generated by the outer balloon, and the fiber dust then settles on the thread or yarn either before, during or after the twisting process and thereby impairs the quality of the twisted thread. In commercial operations where many double twist devices are operated in tandem, a number of protective measures have been proposed in order to prevent the fiber dust from dispersing into all areas and to collect and/ or remove the accumulated fiber dust. For example, attempts have been made to enclose or place a casing around the twisting devices or suction apparatus has been installed for removing the fiber dust as it is formed. However, such measures require substantial changes in the construction of the double twist twisting apparatus and either interfere with the twisting process or else do not provide a satisfactory containment or removal of the fiber dust.

If the outer thread balloon is not permitted to rotate freely but is enclosed or constricted by a stationary balloon-limiting mantle, then there is an appreciably increased formation of flying fiber dust caused by the friction of the twisted thread on the inner surface of the mantle during passage of the thread through the balloon pattern. Nevertheless, it is often essential to employ such a limiting mantle, particularly for the reduction of thread tension in the balloon when working with relatively weak threads composed of staple fibers.

The primary object of the present invention is to provide an improvement in the double twist twisting process and apparatus whereby the formation of fiber dust can be substantially reduced or eliminated. Another object of the invention is to prevent the formation of fiber dust in an economical manner and by a combination of apparatus which can be readily assembled and used with existing installations of double twist twisters. Yet another object of the invention is to avoid the serious problems caused by the formation of fiber dust so as to improve the quality and desirable properties of single or multiple ply twisted thread or yarns composed of staple fibers. It is also a specific object of the invention to realize these and other advantages when twisting relatively weak threads or yarns requiring the use of a balloonlimiting mantle.

Such objects are achieved in accordance with the process of the present invention by continuously applying to the surface of the twisted thread after its emergence from the hollow spindle and before or during passage of the thread through the balloon pattern a small amount of a lubricating agent sufiicient to substantially reduce friction on the twisted thread and loss of fiber ends therefrom. The amount of the lubricating agent applied as a thin coating on the external surface of the thread should be not more than about 2% by weight with reference to the thread, and this amount must be sumciently small to prevent an excess accumulation of the lubricating agent on the surfaces over which the thread passes during the twisting process. In general, satisfactory results are achieved with an amount between about 0.05 and 1.0% by weight, preferably from approximately 0.1 to 0.5% by weight, with reference to the weight of the thread.

The process of the invention is based upon the concept that where it is desired to reduce or prevent the formation of flying dust and flying fibers during double twist twisting, it is essential to reduce and maintain as low as possible the friction of the twisted thread in the balloon. Thus, it is necessary to reduce air friction and also any friction which may be caused by the presence of a balloonlimiting cylindrical mantle or balloon-limiting annular rings or also other guiding surfaces which the thread contacts after it emerges from the spindle. It was generally found that the air resistance of the running and ballooning twisted thread and also its frictional resistance in contact with guiding surfaces can be substantially reduced if the small projecting fiber ends are smoothed down and ad'- hered onto the thread. By applying a uniform, thin coating of the lubricating agent to the thread, the fiber ends no longer stand out at an angle to the axis of the thread, thereby not only reducing friction but also substantially preventing or eliminating the tendency of these fiber ends to break off and from a fiber dust. Furthermore, the friction between the running thread and a balloon-limiting mantle or ring can also be reduced over the whole circumferential inner surface area of the mantle by applying a thin lubricant coating to the running thread and to the surface in contact with the running thread in such a manner that this thin coating is continuously renewed under controlled conditions.

Attempts were made to reduce or prevent flying dust and fibers by applying a finishing agent or a lubricant to the thread on the delivery bobbins, for example by applying such agents by hand on the end surfaces of the bobbins, or else by precoating or prelining the balloon-limiting mantle with a non-adhesive material with a good slipping efiect. Such measures have not provided satisfactory results. For example, in the external coating or brushing of the delivery bobbins with a lubricating agent, the thread does not receive a uniform coating over its entire length, and the thread emerges from the spindle and passes through the balloon pattern with an excess of lubricating agent at some points and only traces of the lubricating agent at other points. A complete soaking or impregnation .of the delivery bobbins is impossible, because the thread take-off from the bobbins is impaired and also because there is substantial interference with the regulation of thread tension in view of the sensitivity of various regulating devices, particularly braking devices, after contact with the thread and excess lubricating agent. It is relatively expensive to line the balloon-limiting mantle with a material presenting a very smooth surface or with a single thick layer of a solid lubricant. Furthermore, such solid lubricant linings over the whole inner surface of the mantle are worn off after a relatively short period of time in contact with the running twisted thread.

The process of this invention differs essentially from the known wet twist processes in that the thread is not impregnated or soaked before imparting a twist to the thread, but instead the lubricating agent is applied only after the initial twisting of the thread emerging from the hollow spindle and then only in a very small or superficial amount onto the external surface of the twisted thread.

By means of the continuous and uniform application of the lubricating agent in accordance with the invention, the surface of the thread is made smooth and even as the protruding fiber ends are brought into alignment with this surface, and the friction of the thread in the balloon is thereby reduced. When it is necessary to employ a balloon-limiting mantle, the lubricated thread as it passes in running contact over the inner mantle surface tends to spread or give off a portion of the absorbed lubricating agent onto this mantle surface, so that during continuous operation the entire inner circumferential surface of the mantle receives a uniform lubricant film capable of further reducing the friction between the twisted thread and the bal Icon-limiting mantle. Also, by providing a continuous supply of the lubricating agent, the lubricating film on the mantle surface constantly renews itself and actually assists in the uniform application of the lubricant to the thread. When working within the essential limitations of this inventions, it is possible to carefully control the continuous supply of the lubricating agent such that excess lubricant does not accumulate on the mantle surface or on similar thread guiding surfaces to the point where this excess might tend to flow off or become dislodged from these surfaces. At the same time, the supply of lubricant can be controlled to provide an external coating on the twisted thread which is just sufficient to provide a smooth thread surface and prevent the formation of flying dust and fibers.

As a lubricant for purposes of this invention, it is possible to employ any of the large number of well known lubricating agents or so-called finishing agents in liquid, pasty or solid form, including various known antistatic oils. It is possible to employ pure or mixed oils as the lubricating agent, and the oil can be applied alone or as an aqueous emulsion or dispersion and if desired with the addition of emulsifiers or antistatic agents. The presence of an antistatic agent is especially helpful in reducing the tendency of the fiber ends to project outwardly from the thread surface.

Specific examples of lubricating or finishing agents include the various known oils, greases or waxes, e.g., the higher aliphatic and aromatic or araliphatic hydrocarbons as well as related substances. Such lubricating oils may be obtained from natural sources such as tallow and other glyceride oils and fats, olive oil, castor oil, linseed oil, mineral oils such as paraffin oil or white oil, and the like. Finishing agents in the form of aqueous emulsions of a lubricating agent can also be employed and include such materials as emulsified natural oils or fats, sulfonated oils such as tallow sulfonates, wholly or partially saponified oils and fats, fatty alcohol sulfonates, fatty acid sulfonates', fatty acid condensation products, organo-silicones such as alkyl, arylor aralkyl-silicones, and polyoxyalkylatedfatty alcohols, -fatty acids or -fatty amines. Such lubricating agents, emulsifiers and antistatic agents have been described in literature references in considerable detail, for example as disclosed in Surface Active Agents by Schwartz and Perry, Interscience Publishers, Inc., New York, 1949, pages 423426. Any suitable lubricating agent or composition can be readily selected for the purposes of the present invention, although liquid lubricants are especially useful in the preferred embodiments of this invention. If desired, one can employ a lubricating agent which can be easily washed from the surface of the twisted thread after it has passed through the balloon pattern. Extensive washing is not required for such removal of the lubricating agent because of the small amount employed, and the process of the invention is therefore readily adapted to the production of an essentially dry twisted thread.

For the purposes of this invention, apparatus can be constructed according to a number of different embodiments or combinations, all of which can be readily adapted to conventional double twist thread twisting devices which have a hollow bobbin spindle and means for guiding the twisted thread into an outer balloon pattern. In general, the apparatus of this invention essentially requires in combination with said spindle and guide means a continuous supply means for coating the lubricating agent onto the external surface of the twisted thread, this supply means being located adjacent to the path of the twisted thread as it emerges from the hollow spindle and passes into and through the outer balloon pattern.

More specifically, the double twist twisting apparatus of the invention can include a rotating twisting head at the lower end of the hollow spindle as a means for twisting and guiding the thread into the outer balloon pattern, the twisting head being constructed as a 'hollow container capable of holding a supply of the lubricating agent and having one or more passageways leading outwardly to the outer surface of the twisting head which wall.

is in contact with the running thread. The combination of apparatus may also include a conventional balloonlimiting or balloon-guiding mantle or ring concentric with the spindle axis, this mantle or ring being modified to act as a container capable of holding a supply of the lubricating agent and to have one or more passageways leading inwardly to the surface in contact with the running twisted thread.

It is especially advantageous to employ a combination of apparatus in which the double twist twisting device is provided with a conventional balloon limiting mantle constructed in the form of an elongated cylindrical shell surrounding at least the upper portion of the spindle and having an inner circumferential surface which is concentric with the spindle axis and contacts the ballooning twisted thread in order to constrict the balloon pattern. In accordance with the invention, at least one supply vessel or container for the lubricating agent is arranged on the outer circumferential surface of this mantle, there being one or more passageways or overflow outlets for conducting lubricant from the container to the inner surface of the mantle wall. Where a large number of twisting devices with such mantles are arranged in tandem, as in commercial practice, a single pipeline or conduit can be arranged along side the mantles and connected to each lubricant container by means of a branching conduit so that the lubricating agent can be continuously or periodically supplied to each container. This supply line can be adapted to fill each container with liquid lubricating agent to a predetermined level so as to maintain a continuous supply of the lubricant at all times.

The passageways or outlets for conducting the lubricating agent to the surfaces in contact with the running twisted thread, regardless of the particular combination employed, may be constructed in the form of narrow slits, finely drilled openings or hair gaps or as relatively large openings tapering up to a fine aperture at the thread running surface. On the other hand, the passageways can also be formed by providing a porous wall along at least a portion of the surface in contact with the running thread. In the preferred construction having a balloon-limiting mantle, the passageways are preferably formcd by a slot or opening in the mantle Wall and a porous or absorbent material in the form of a wick or the like arranged in this opening and adapted to transfer the lubricating agent so as to emerge from the carrier in alignment with the inner surface of the mantle In this case, the carrier or wick-like material acts as the conduit or passageway for the lubricating agent from the container onto the thread in contact with the inner surface of the mantle. A liquid or pasty lubricat ing agent, including aqueous emulsions of lubricating agents, can be continuously supplied in this manner onto the external surface of the thread so as to smooth down the protruding fiber ends and simultaneously distribute the lubricating agent on the surfaces in contact with the thread balloon. A constant and uniform application of the lubricating agent onto the thread and the thread contacting surfaces of the mantle can be achieved by maintaining a uniform content of lubricating agent in the container and by providing means to regulate the rate at which the lubricating agent flows through the porous carrier material.

Suitable carrier materials include fibrous or fabric tows or wicks, felts, natural or synthetic sponges or similar foamed or cellular structures, or even a sintered material such as a sintered ceramic pack inserted into the lubricant container. For example, the container can be completely packed with a fabric, felt or tow of hemp,

which has been filled into the container so as to provide a liquid surface level somewhat below the lower end of the slot or opening. The wick can be held in the slot or opening with means including a leaf spring or similar structure adapted to apply pressure or compression on the wick and thereby regulate the rate of flow of liquid through the wick. The rate of flow can be regulated by varying the pressure placed upon the wick, e.g., by means of an adjustable screw to change the tension of the leaf spring. The wick in the form of a felt or fabric strip should fit snugly into the slot or opening such that the thread-coating surface of the wick is even and forms a continuous surface with the inner mantle surface.

The rate at which the lubricating agent is coated onto the twisted thread can also be influenced by using fine slits or apertures of different sizes and means to supply the lubricating agent alternatively to one or the other of the different sizes of apertures. Similarly, the size of the aperture can be made adjustable by inserting plugs therein or by pushing a carrier material into a relatively small aperture and adjusting the pressure on the carrier material in a manner similar to the application of pres sure to the above-described wick.

Of course, more or less lubricating agent will be applied to the twisted thread depending upon the number and size of the passageways leading to the surfaces in contact with the running twisted thread. These factors can be calculated or closely approximated from the amount of lubricating agent which must be applied to the thread over a given period of time, and the exact dosage of the lubricating agent can then be regulated by any suitable means for adjustably decreasing or increasing the size of the opening or adjustably controlling the rate of flow through each passageway. As a practical matter, it is advantageous to increase the rate of flow of the lubricating agent and its application to the twisted thread up to that amount which is just sufficient to give the desired results without spreading an undesirable excess of lubricating agent onto the thread contacting surfaces.

By means of the continuous and uniform application of the lubricating agent as a thin coating: on the twisted thread, the surface of the thread becomes quite smooth and free of protruding fiber ends, thereby passing more freely and with less resistance through the balloon pattern. Since the twisted and lubricated thread redistributes a large proportion of the lubricating agent back onto the thread-guiding or balloon-limiting surfaces, it is possible to simultaneously provide a thin lubricant coating on such surfaces and the friction between the twisted thread and the balloon-limiting mantle or ring is thereby additionally reduced by an appreciable amount. It was quite surprising to discover that this very superficial lubrication of the twisted thread not only reduces friction but also substantially completely eliminates the undesired accumulation of flying fibrous dust. The fiying fibers or dust are not merely captured or trapped by the lubricant on the thread and balloon-limiting surfaces, but instead the formation of the flying dust is itself prevented and the apparatus and also the thread remain entirely clean and free of such dust over very long periods of operation.

The process and apparatus of the invention are particularly advantageous where twisting threads composed of synthetic staple fibers or mixtures of staple fibers which are especially characterized by their tendency to form a large number of protruding fiber ends. Where the properties of elongation and tensile strength of the twisted thread were previously impaired and reduced below tolerable limits, due to the friction of the thread in the balloon-limiting mantle, these properties are now preserved in a satisfactory manner after reduction of friction in accordance with the invention.

The invention is further illustrated by the following detailed description of specific apparatus taken in conjunction with the accompanying drawings, wherein similar parts have been designated by the same reference numerals and wherein:

FIG. 1 is a partly schematic side elevation in partial diametric cross section of a double twist twisting apparatus illustrating one embodiment of the invention in which the balloon-limiting mantle is provided with a lubricant container;

FIG. 2 is a cross sectional view taken on line IIII of FIG. 1, illustrating the balloon-limiting mantle and container with other elements of the apparatus being omitted;

FIG. 3 is a top plan view of three balloon-limiting mantles in accordance with the invention, the corresponding spindles and other elements of the double twist de vices being omitted, with a single supply conduit passing along each of the mantles;

FIG. 4 is a side elevation of another embodiment of a double twist twisting apparatus constructed in accordance with the invention to provide a hollow twisting head as the lubricant container;

FIG. 5 is a side elevation in partial diametric cross section of still another embodiment of the double twist twisting apparatus of the invention wherein the lubricant container is formed by a hollow or tubular ring which also serves as a balloon-guiding surface;

FIG. 6 is a cross sectional view of a portion of the wall of the lubricant container illustrating various passageways or apertures in this wall;

FIG. 7 is a side elevation with portions omitted of two mantle containers and a central supply container equipped as a dosing device for supplying a uniform level of liquid lubricating agent in each of the mantle containers;

FIG. 8 is a side elevation with portions omitted of a mantle container equipped with a leaf spring as pressure means for adjusting the flow of lubricant through a carrier wick; and

FIG. 9 is a cross sectional view taken along line IX- IX of FIG. 8.

In the double twist twisting device of FIG. 1, there are shown a stationary bobbin carrier or holder 1, a rotating head or twist guide 2 and whorl 2a, arranged in conventional manner. The threads T are drawn off laterally from the adjacent rotatably mounted delivery bobbins 3 and 4, conducted through the guide eyelets 5 and 6 on the protective basket or cage 7, and then led over the thread guide roller 8 into the thread inlet of the hollow spindle 9. The combined threads T are then conducted downwardly through this hollow spindle and emerge radially therefrom over the rotating accumulator disc 10 and the twist guide 2 into a rotating balloon pattern 11. Finally, the twisted threads pass through the guide eyelet 12 and in the direction of the arrow to a preliminary drawoff device or take-up reel (not shown). These elements are all conventional in apparatus of this type, and as is well known, the threadsreceive a double twist as they are drawn through the illustrated path.

The twisting device is further equipped with a cylinder mantle or shell 13 constructed according to the invention. This mantle provides a concentric enclosure around the spindle and bobbins and limits the outer thread balloon 11 by contact of the running thread with the inner cylindrical surface 14. As shown in FIG. 2, the mantle is provided with a longitudinal slit 15 for purposes of threading the apparatus. This much of the mantle is constructed and arranged as in many conventional double twist twisters. In order to accomplish the objects of the present invention, there is arranged on the outer circumferential surface of the balloon-limiting mantle 13 and integral therewith a container 16 adapted to hold a supply of a lubricating agent and/or an inert carrier material adapted to absorb and distribute the lubricating agent. Any suitable carrier material can be employed such as the sponge packing 29 shown in the container mounted on the mantle 20 of FIG. 3. In the mantle wall forming part of the lubricant container 16, a passageway is provided in the form of a narrow slit 17 through which the lubricating agent flows from the container onto the twisted thread passing through the balloon 11 and is further spread as a thin film on the inner circumferential surface 14 of the mantle.

Where a plurality of twisting devices are employed in a tandem or series arrangement, it is possible to provide an intermittent or continuous supply of lubricating agent to each of the containers of the corresponding series of mantles as indicated in FIG. 3. The twisting apparatus itself has been omitted from FIG. 3 to avoid unnecessary detail, and a series of three balloon-limiting mantles 18, 19 and 20 are shown in their individual stalls formed by the stationary separating plates or partitions 21. Each mantle contains a supply vessel or container 16 and is provided with the narrow slit or aperture 17. Individual supply lines or conduits 22, 23 and 24 conduct fresh lubricating agent into each of the containers from a common supply line or conduit 25 connected to the gear wheel conveyor pump 30. The mantle 19 in the middle of this series has a container which is empty as in FIG. 1 and FIG. 2. A cover or lid 28 is placed over the container on the left-hand mantle 18 and this cover is provided with an opening for the supply line 22. On the right-hand mantle 20, the container 16 is shown with an insert or packing of any suitable carrier material 29.

In FIGS. 4 and 5, two additional embodiments of the invention are illustrated in order to indicate other possible means of providing a container for the lubricating agent. With reference to FIG. 4, the twist guide 2 has a hollow interior 26 serving as a circular container for the lubricating agent. With reference to FIG. 5, an annular container for the lubricating agent is provided in the form of a tubular ring 27 which is concentric with the spindle axis and is located adjacent the outer periphery of the bobbin holder 1. In both of these figures, there is only a single delivery bobbin 3 for twisting a single thread which passes downwardly through the hollow spindle 9, outwardly over the accumulator or reserve disc 10 and then into the balloon pattern 11 where the thread is drawn off through the top eyelet 12 in the direction of the arrow. Lubricant containers of these types can be used in the absence of a cylindrical balloon-limiting mantle or shell, but it will also be obvious that these containers can also be used in combination with a cylindrical mantle. The lubricant containers in each of these figures can be filled with fresh lubricant by any suitable connection with a supply conduit or by simply refilling through an opening normally closed off by a screw plug. Of course, each of these containers must be provided with passageways or openings leading from their hollow interior to the surface in contact with the running twisted thread.

FIG. 6 provides an illustration of several different types of fine bores or drillings, as generally indicated by the numeral 17, in a fragmentary cross-sectional view of the mantle Wall 13 with its inner lubricated surface 14. The passageway 17a is a finely drilled hole tapering inwardly to the lubricating surface 14. Passageway 17b is formed by a small bore of constant diameter which is enlarged on the container side of the mantle wall. Several small bores or finely drilled holes 17c can also be combined into a single enlarged opening. Several rows of such finely drilled passageways can be spaced uniformly or in a random pattern in the mantle wall of the container, and in order to regulate the flow or supply of lubricating agent, it is possible to use a metal or plastic insert, e.g., in the form of a stencil, which is capable of blocking off individual openings or a single row of openings in a predetermined pattern. Of course, it is also possible to use an inert carrier material capable of at least being inserted in the enlarged portion such as that connecting the bores 17c, on the flow rate can be regulated by means of an adjustable leaf spring or the like adapted to press against the carrier material. Fine openings of this type can also be employed with the specific lubricant containers shown in FIGS. 4 and 5, for example by one or more rows of such openings around the outer periphery of the twisting head 26 or the inner periphery of the annular ring 27.

FIG. 7 sets forth a combination of apparatus which is adapted to provide a continuous supply of lubricating agent from a centrally located supply tank 31 to at least two or more mantle containers 16, suitable means being provided to maintain a constant level of the lubricating agent in each of the mantle containers. Only the essential components of this combination are illustrated in FIG. 7, a twisting device being associated with each of the mantles substantially as shown in FIG. 1. In this particular embodiment of the invention, a carrier material in the form of a wick 38 is fitted snugly into the opening 17 in the mantle wall 13, and this wick extends downwardly into the bottom of the container 16. The level of the liquid lubricating agent can be maintained slightly below the opening 17 such that the liquid is carried upwardly through the wick so as to emerge in alignment with the inner surface of the mantle 13.

The supply tank 31 (shown empty in FIG. 7) has a slotted neck fitted with a slideable valve means for maintaining a constant level of liquid in the supporting trough for holder 33, this valve means operating as in corresponding devices commonly used as a continuous water supply for an animal feeding trough. With liquid in the tank 31 and the trough 33 filled to the desired level, the spring actuated valve 32 is forced downwardly to a closed position, and liquid is transferred from the trough 33 through tubes such as 35 and 36 into two or more mantle containers 16 where the liquid reaches the same level as that in the trough. Then, as the liquid level 37 in the trough goes down, the valve means slides down the neck of the tank 31, and the valve stem 34 pushes the valve 32 to an open position permitting liquid to flow into the trough until the desired liquid level is again established. In this manner, each mantle container can be supplied with the proper amount of lubricating agent from a continuous source over a long period of time.

FIGS. 8 and 9 provide one illustration of adjustable means to regulate the flow of the lubricating agent through a carrier material in the form of a wick 38 onto the external surface of the thread as it brushes against this wick in the rotating balloon pattern. Thus, if the wick is compressed or placed under pressure, the flow of liquid lubricating agent can be diminished, while a release of this pressure will increase the flow rate. In order to accomplish this result, a backing plate or strip 39 is placed over the wick 38 and held in place by the leaf spring 40 attached by means of screws 41 and 42 which tighten the brackets 43 and 44 against the leaf spring. By adjusting screw 42, the leaf spring 40 compresses the wick 38 at its lower end between the packing plate 39 and the mantle wall 13. The amount of compression obtained by tightening this screw 42 determines the extent to which the flow rate of lubricating agent is diminished, since the compression reduces the size of the capillary or cellular passages in the wick. Of course, other means can also be employed to compress the carrier material of the wick, and other modifications having the same function can be readily adapted by those skilled in the art. The leaf spring arrangement shown in the drawing has the advantage that a relatively uniform pressure can be placed over the entire portion of the wick contained in the opening 17, as where both ends of the plate 39 are freely movable and both screws 41 and 42 can be tightened or loosened in order to regulate the amount of compression.

Although the exact manner of using the apparatus for the process of the invention has been explained in detail by the foregoing description, some typical examples using diiferent lubricating agents in the apparatus of FIGS. 1 and 2 can be briefly recounted as follows:

As the initial thread wound delivery bobbins 3 and 4, there were used wool-polyester mixed threads Nm 402 having in each case a preliminary twist of 600 Z. These threads are initially employed without any special preparation, i.e., they were substantially dry and relatively free of any adhering moistening or finishing agents. The balloon-limiting mantle 13 had a height of 195 mm. and was provided with a slot 17 as a passageway for the lubricant which was 75 mm. long and 1.5 mm. wide. The lower edge of this slot was located mm. from the top edge of the mantle. As a wick, there was pressed into this slot a correspondingly shaped felt strip 5 mm. in width and 10 mm. in depth. As the lubricating agent, a liquid oil identified as Lysolfix was used. The threads were twisted together on this double twist twisting apparatus so as to provide 640 additional Z turns. The amount of lubricant applied to the twisted thread was 0.27% of the thread weight. In the twisting process, no flying dust or fibers could be observed, the friction on the twisted thread in the balloon pattern was noticeably reduced, and the interior surface of the mantle retained a very thin coating or film of lubricant over the extended period of operation.

Equally good results were achieved when using a lubricating oil identified as Tallopol, the lubricant being applied in this case in an amount of 0.42% by weight with reference to the twisted thread weight. Also, substantially the same results were observed when using an aqueous emulsion of the lubricating oil identified as Lysolfix in an oil to water ratio of 1:1. The amount of lubricant emulsion applied and retained on the external surface of the twisted thread in this case was 0.34% of the thread weight.

The process and apparatus of the invention are thus easily and inexpensively combined with conventional double twist twisters while achieving all of the desired advantages and improvements as previously described. Even after several months of operation, the interior of the mantle remains completely clean, and there is no damaging accumulation of fiber dust or excess lubricating agent. Various modifications can of course be made in the process and apparatus of the invention by one skilled in this art without departing from the spirit of the invention or the scope of the appended claims.

The invention is hereby claimed as follows:

1. In a double twist twisting process in which thread composed of staple fibers is drawn from at least one delivery bobbin for passage downwardly through a hollow bobbin spindle and then outwardly as twisted thread into a ballon pattern, the step comprising: continuously applying to the outer surface of the twisted thread solely from a thread guiding surface which is in contact with the twisted thread as it is conducted upwardly into and through said balloon pattern a small amount of a lubricating agent sufficient to substantially reduce friction on said twisted thread and loss of fiber ends therefrom.

2. A process as claimed in claim 1 wherein the amount of said lubricating agent applied to the surface of the twisted thread is between approximately 0.05 and 1.0% by weight with reference to the thread.

3. A process as claimed in claim 1 wherein the amount of said lubricating agent applied to the surface of the twisted thread is about 0.1 to 0.5% by weight with reference to the thread.

4. A process as claimed in claim 1 wherein said lubricating agent is applied to the twisted thread from a thread guiding surface at the lower end of said balloon pattern.

5. A process as claimed in claim 1 wherein said lubricating agent is applied to the twisted thread from the inner surface of a balloon limiting mantle which is in contact with the thread balloon.

1 Lysolfix and Tallopol are compositions consisting essentially of super-refined mineral oil (type Vaseline oil or paraffin oil) with approximately 5 to 10% emulsifiers as the liquid oily lubricating agent.

6. In combination with a double twist thread twisting apparatus having a hollow bobbin spindle and a thread contacting surface for upwardly guiding the twisted thread into and through an outer balloon pattern, continuous supply means for coating a small amount of lubricating agent onto the external surface of said twisted thread from said thread contacting surface, said supply means being located adjacent to and in liquid connection with said thread contacting surface.

7. The combination as claimed in claim 6 including a thread guide member at the lower end of the balloon pattern, the outer thread contacting surface of said guide member being in liquid communication with said supply means so as to coat the twisted thread while in contact with the outer surface of said guide member which guides the twisted thread upwardly into the balloon pattern.

8. The combination as claimed in claim 6 including a balloon limiting mantle having an inner thread contacting surface in liquid communication with said supply means so as to coat the twisted thread while in contact with said limiting mantle and during passage through said balloon pattern.

9. A double twist twisting apparatus comprising: a spindle adapted to hold at least one delivery bobbin of thread and having a longitudinal bore for the passage of thread downwardly therethrough; and means for twisting said thread including a rotating twisting head at the lower end of said spindle, said thread being in running Contact with the outer surface of said twisting head and being guided thereby in twisted form outwardly from said spindle into an outer rotating balloon pattern, said twisting head being adapted to contain a supply of lubricating agent and having at least one passageway for conducting said lubricating agent outwardly to the outer surface thereof in contact with the running twisted thread.

10. A double twist twisting apparatus comprising: a spindle adapted to hold at least one delivery bobbin of thread and having a longitudinal bore for the passage of thread downwardly therethrough; means for twisting said thread including a rotating twisting head at the lower end of said spindle, said thread being in running contact with the outer surface of said twisting head and being guided thereby in twisted form outwardly from said spindle and upwardly into an outer rotating balloon pattern; a mantle around said spindle With an inwardly facing surface for contact with the running thread and for limiting the outward ballooning of said thread; and at least one container capable of holding a supply of thread lubricating agent, each container being located adjacent to and in liquid communication with one of the surfaces which is in contact with the upwardly running twisted thread.

11. A double twist twisting apparatus comprising: a spindle adapted to hold at least one delivery bobbin of thread and having a longitudinal bore for the passage of thread downwardly therethrough; means for guiding said thread outwardly from said spindle into an outer balloon pattern; and a mantle around said spindle with an inwardly facing surface for contact with the running thread and for limiting the outward ballooning of said thread, said mantle being constructed to hold a supply of thread lubricating agent and having at least one passageway for conducting said lubricating agent inwardly to the inner surface thereof in contact with the running twisted thread.

12. An apparatus as claimed in claim 11 wherein said mantle is constructed in the form of a tubular ring serving as an annular container for said lubricating agent.

13. An apparatus as claimed in claim 11 wherein said mantle is constructed in the form of an elongated cylindrical shell concentric with the spindle axis and has at least one container for supplying said lubricating agent arranged on the outer circumferential surface thereof.

14. An apparatus as claimed in claim 11 including means to continuously supply said lubricating agent from said mantle onto the running thread at a uniform predetermined rate.

References Cited by the Examiner UNITED STATES PATENTS 3,159,962 12/1964 Franzen 5758.83 X

FOREIGN PATENTS 594,542 3/1934 Germany.

FRANK J. COHEN, Primary Examiner.

STANLEY N. GILREATH, Examiner.

D. E. WATKINS, Assistant Examiner. 

6. IN COMBINATION WITH A DOUBLE TWIST THREAD TWISTING APPARATUS HAVING A HOLLOW BOBBIN SPINDLE AND A THREAD CONTACTING SURFACE FOR UPWARDLY GUIDING THE TWISTED THREAD INTO AND THROUGH AN OUTER BALLOON PATTERN, CONTINUOUS SUPPLY MEANS FOR COATING A SMALL AMOUNT OF LUBRICATING AGENT ONTO THE EXTERNAL SURFACE OF SAID TWISTED THREAD FROM SAID THREAD CONTACTING SURFACE, SAID SUPPLY MEANS BEING LOCATED ADJACENT TO AND IN LIQUID CONNECTION WITH SAID THREAD CONTACTING SURFACE. 